Proximity detector comprising capacitive sensor

Proximity detector employing a capacitive sensor, comprising:

• at least one detection antenna comprising a plurality of capacitive proximity sensors, each comprising a measurement electrode and a shield, said antenna being placed close to an object or a body;
• electronic means for exciting said measurement electrodes and for processing the signals originating from said capacitive sensors;
• digital means for controlling the electronic means and for calculating, from the measurement signals thus processed, the distances between said electrodes and said object or said body;
• said electronic means comprising, for each detection antenna, a floating capacitive bridge or with floating excitation, cooperating with polling means to measure sequentially the respective capacitances between each electrode of said antenna and the object or body to be measured,
• wherein at least one of the detection antennas comprises a test track which, in normal operation, is at the potential of the shield and, in test mode, is earthed.

Proximity detector employing a capacitive sensor, comprising:

• at least one detection antenna comprising a plurality of capacitive proximity sensors, each comprising a measurement electrode, said antenna being placed close to an object or body to be measured;
• electronic means for exciting said measurement electrodes and for processing signals originating from said capacitive sensors;
• digital means for controlling said electronic means and for calculating, from measurement signals thus processed, distances between said electrodes and the object or body;
• wherein said electronic means comprise, for each detection antenna, a floating capacitive bridge or with floating excitation, cooperating with polling means to measure sequentially the respective capacitances between each said electrode of said antenna and the object or body
• wherein the proximity detector is used in a piece of radiology equipment employing X-rays and comprising a device for emitting an X-ray beam intended to irradiate the object or body and a device for detecting the X-rays originating from the object or body, said detector device being covered by a cap, the proximity detector being arranged on the inside or outside surface of said cap,
• wherein said detection antenna comprises a flexible printed circuit composed of an insulator metallised on both faces with a thin layer of chromium then by a layer of copper, said copper layer being removed over an area which corresponds to a passage for the X-ray beam and in which linking tracks and the capacitive proximity sensors are produced from the chromium layer.